From the datasheets, it looks like the principal difference is that the 4200 has "programmable digital blocks" which are basically micro-FPGA's, programmable in

From the datasheets, it looks like the principal difference is that the 4200 has "programmable digital blocks" which are basically micro-FPGA's, programmable in Verilog. I'm not sure how capable they actually are but it's a pretty cool idea. 4100: http://www.cypress.com/?docID=46324 http://www.cypress.com/?docID=46324 4200: http://www.cypress.com/?docID=46322 http://www.cypress.com/?docID=46322